Once Clutter is enabled in the Outlook web app, it appears in other clients linked to that Exchange account, including the Outlook client on both Windows and OS X desktops and notebooks, and the iPhone and Android Outlook on the web apps.
Users can drag messages they deem suitable to the Clutter folder to "train" the tool to spot similar email in the future. The tool gets smarter over time, learning from your prior actions with similar messages.
If Exchange is missing messages you want marked as clutter, right click and choose 'Mark as clutter' or drag it to the Clutter folder. In Outlook and other clients, you’ll need to drag a message to the clutter folder to mark it as clutter or drag it to th… Read more about How do I mark a message as clutter?
Most of the mail going into the folder should be bulk mail (advertisements) and messages from mailing lists. However, you will want to periodically check the Clutter folder as it may move legitimate email into this folder.